Pippa 'to move in with boyfriend'

The 28-year-old brunette - the sister of Britain's Duchess Catherine - has been given a set of keys to Alex Loudon's apartment in west London and has moved many of her belongings into the property.

A friend told the Mail on Sunday newspaper: "They are very much an item and Pippa tends to stay at his place on a Wednesday, Thursday and often Friday night.

"She has her own place in Chelsea and she splits her time between their houses, but she's spending more time at Alex's these days. She's moved some of her things in and he has given her a set of keys so Pippa comes and goes as she pleases.

"Alex absolutely dotes on her and they are really very serious.

"They do spend a lot of time together but they like to keep their romance under the radar. Alex particularly doesn't like lots of fuss and he finds the interest in their relationship baffling and somewhat bemusing."

The couple - who have been dating for three years - recently celebrated Pippa's birthday with her parents, Catherine, her husband Prince William and Alex has the approval of all of his girlfriend's loved ones, fuelling speculation they will marry.

The source said: "They had a lovely, low-key evening. After a pasta dinner and a birthday cake, they went back to Pippa's house for cocktails.

"William, Kate and Pippa's parents adore Alex. They trust him and see him as one of the family. They'd be very happy if he slipped a ring on Pippa's finger."

Another source added: "Pippa is very much in love with Alex and she may well end up marrying him."